These studies are directed toward understanding the basic mechanisms involved in the initial host-parasite interaction (i.e. colonization of a tooth or mucosal surface). We are attempting to study the parameters which influence these adherent interactions and to identify, isolate and characterize the surface receptor molecules which mediate the adherence of some important periodontopathogens to teeth and oral mucosal. Ultimately, we anticipate that information obtained from these studies can be applied toward developing immunologic approaches for preventing colonization by these potential peirodopathogens.